Making Predictions (11-5)

Making Predictions

Vocabulary

Prediction- something you can reasonably expect to happen in the future.

Video Help

https://www.youtube.com/watch?v=W2edvqASX94

https://www.youtube.com/watch?v=NFSDhLNog6U

https://www.youtube.com/watch?v=X1hfNR6redg

Examples

Sometimes it is difficult to determine the probability of an event because you don't know all the possible outcomes or you don't know how likely each outcome is. In these circumstances, you can sometimes collect data and predict the probability based on the data.

A sample is a set of data that can be used to predict how a particular situation might come about. You can use sample data to determine probability.

Example 1

The student council collected data to see what kind of snacks were chosen most often by the students. Based on the data, what is the probability that students will choose potato chips? Type of snack Number ordered Pretzels 80 Potato chips 70 Tortilla 60 Cheese puffs 40 Cookies 100 There were 350 bags of snacks chosen. Of the 350 bags, 70 were potato chips. So, you can expect 70/350, or 1/5, of the students to order potato chips.

Example 2

The manager of the pizza shop wanted to know what kind of pizza slices customers order during lunch. She collected this data during one lunch session. Suppose 200 customers are expected in one week. Use the data to estimate how many cheese slices will be ordered in a week. Pizzas Slices Ordered Pepperoni 25 Sausage 10 Cheese 50 Mushroom 15 There were 100 slices ordered. Of the 100 slices, 50 were cheese. The probability of a customer ordering a cheese slice is 50/100, or 1/2. Write and solve a proportion. number of ways event can happen number of possible outcomes  1  =     x     2       200     2x =  200     x  =  100 About 100 customers a week could be expected to order a cheese slice.

Remember: When a probability is to be written as a fraction, the fraction should be written in lowest terms.